package myEclipseGen;
import java.io.BufferedReader;   

import java.io.IOException;   

import java.io.InputStreamReader;   

public class MyEclipseGen {   

private static final String LL = "Decompiling this copyrighted software is a violation of both your license agreement and the Digital Millenium Copyright Act of 1998 (http://www.loc.gov/copyright/legislation/dmca.pdf). Under section 1204 of the DMCA, penalties range up to a $500,000 fine or up to five years imprisonment for a first offense. Think about it; pay for a license, avoid prosecution, and feel better about yourself.";   

public String getSerial(String userId, String licenseNum) {   

   java.util.Calendar cal = java.util.Calendar.getInstance();   

   cal.add(1, 3);   

   cal.add(6, -1);   

   java.text.NumberFormat nf = new java.text.DecimalFormat("000");   

   licenseNum = nf.format(Integer.valueOf(licenseNum));   

   String verTime = new StringBuilder("-").append(new java.text.SimpleDateFormat("yyMMdd").format(cal.getTime())) .append("0").toString();   

   String type = "YE3MP-";   

   String need = new StringBuilder(userId.substring(0, 1)).append(type).append("300").append(licenseNum).append(verTime).toString();   

   String dx = new StringBuilder(need).append(LL).append(userId).toString();   

   int suf = this.decode(dx);   

   String code = new StringBuilder(need).append(String.valueOf(suf)).toString();   

   return this.change(code);   

}   

private int decode(String s) {   

   int i;   

   char[] ac;   

   int j;   

   int k;   

   i = 0;   

   ac = s.toCharArray();   

   j = 0;   

   k = ac.length;   

   while (j < k) {   

    i = (31 * i) + ac[j];   

    j++;   

   }   

   return Math.abs(i);   

}   

private String change(String s) {   

   byte[] abyte0;   

   char[] ac;   

   int i;   

   int k;   

   int j;   

   abyte0 = s.getBytes();   

   ac = new char[s.length()];   

   i = 0;   

   k = abyte0.length;   

   while (i < k) {   

    j = abyte0[i];   

    if ((j >= 48) && (j <= 57)) {   

     j = (((j - 48) + 5) % 10) + 48;   

    } else if ((j >= 65) && (j <= 90)) {   

     j = (((j - 65) + 13) % 26) + 65;   

    } else if ((j >= 97) && (j <= 122)) {   

     j = (((j - 97) + 13) % 26) + 97;   

    }   

    ac[i] = (char) j;   

    i++;   

   }   

   return String.valueOf(ac);   

}   

public MyEclipseGen() {   

   super();   

}   

public static void main(String[] args) {   

   try {   

    System.out.println("please input register name:");   

    BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));   

    String userId = null;   

    userId = reader.readLine();   

    MyEclipseGen myeclipsegen = new MyEclipseGen();   

    String res = myeclipsegen.getSerial(userId, "5");   

    System.out.println("Serial:" + res);   

    reader.readLine();   

   } catch (IOException ex) {   

   }   

}   

}  